Now that all targets have been converted to nrun, we can finally punt
this old inconsistent interface.
A few stray references to the old run were sprinkled about; clean them
up in the process.
We leave behind the run(1) man page mostly so that we get it updated for
the new nrun interface.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.